Why is heart disease one of the major killers of the world?

Exercise/diet: As countries become more "western", they exercise less and eat a high-fat diet. When a third world countries becomes more like the United States, they exercise less, drive around in cars, and eat a fatty diet. Subsequently, they develop heart attacks, congestive heart failure, and heart disease becomes the leading cause of death.

Major killer in USA : More than 80 million american have one or more cardiovascular disease. Cardiovascular dz accounts for 1 if every 3 deaths in usa. Coronary artery disease account for 1 in every 5 deaths in usa. CAD is the leading cause of death in 65 y/o and older americans. And 2nd only to cancer for americans between 45 -64 y/o. Cost of is close to 500 billion dollars a year. I am an american and this worry me.